U.S. Pat. No. 5,376,410 (MacKelvie) purports to disclose a method for treating a surface which is to be bonded to another surface. The method comprises displacing a portion of the surface material to a position such that the displaced material, while remaining an integral part of the surface, forms a burr which is adapted to mechanically engage a flexible material placed adjacent thereto to thereby provide a mechanical interlocking action.
European Patent Application Publication No. EP0859163A1 (Sundheim) purports to disclose a pad holder that is a structure made of a heat-resistant foamed material, especially aluminum foam, with a sheet of high strength metallic material, especially a steel sheet. The structure may be a sandwich-like composite consisting of a structural layer of the foamed material, which at least on one side is bonded with a steel sheet.